This application claims the priority benefit of Taiwan application serial no. 90130499, filed Dec. 10, 2001.
1. Field of the Invention
The invention relates in general to a substrate exposure apparatus, and more particularly, to a substrate exposure apparatus that uses a display apparatus to directly perform exposure on the photoresist.
2. Description of the Related Art
Photolithography process is one of the crucial steps in the IC substrate, printed circuit board, and semiconductor fabrication process. In wafer fabrication, the patterned and doped regions for each thin film layer are determined by photolithography process. Also, the formation of metal film patterns in printed circuit board and IC substrate are determined by photolithography process. And, for each one, the photomask must be well prepared. In photolithography process, after some preparation process, the photoresist is coated on the substrate and soft bake and hard bake are further performed. After the photoresist is cured, the steps of exposure and development are performed to transfer the pattern of the photomask to the photoresist.
Referring to FIG. 1, a conventional photolithography process that uses a contact mode photomask to transfer the pattern to the photoresist is schematically shown. A substrate 100, on which a circuit, dielectric layer, dielectric pattern or conductive layer may have been formed, is provided. A photoresist 102 is formed on the substrate 100. A photomask 110 is disposed on the photoresist 102. To protect the surface of the photomask 110, a protect film 104 is placed between and separates the photomask 110 and the photoresist 102. The protect film 104 is in contact with both the surface of the photomask 110 and the photoresist 102. By radiation of a light source 112, an exposure step is performed on the photoresist 102, so that the pattern of the photomask 110 is transferred to the photoresist 102.
The conventional contact mode photomask 110 includes formation of a patterned blocking layer 108 on a surface of a transparent substrate 106. To protect the photomask 110, the protect film 104 sandwiched between the photomask substrate 106 and the photoresist 102 is in contact with both surfaces of the photomask substrate 106 and the photoresist 102. The patterned blocking layer 108 of the photomask 110 blocks the light source 112 to determine the pattern on the photoresist 102 to be radiated.
Referring to FIG. 2, a conventional photolithography process using a non-contact mode photomask to transfer a pattern to a photoresist is schematically shown. A substrate 200 on which a photoresist 202 is formed is provided. Circuits, dielectric layers, dielectric patterns or conductive layers may have been formed on the substrate 200. A photomask 210 is located above the photoresist 202. A lens set 214 is disposed between the photomask 210 and the photoresist 202. By radiation of a light source 212, the photoresist 202 is exposed, and the pattern of the photomask 210 is transferred to the photoresist 202.
The conventional non-contact mode photomask is constructed by forming a patterned blocking layer 208 on a transparent substrate 206. The patterned blocking layer 208 on the transparent substrate 206 blocks the light source to determine the pattern of the photoresist 202 to be radiated. In a non-contact mode, the pattern of the photomask 210 is transferred to the photoresist 202 by the lens set 214.
The fabrication of the conventional photomask is very time consuming and costly. The photomask has to be kept in an appropriate environment, and the maintenance cost is also high.
In addition, the pattern of the photomask cannot be modified. When the circuit design of the wafer or printed circuit board requires a modification, a new photomask has to be fabricated.
The present invention provides a substrate exposure apparatus that does not require a photomask. The fabrication cost and maintenance cost of a photomask in the photolithography process are thus saved.
The present invention further provides a patternable substrate exposure apparatus, in which the displayed pattern is easily modified according to the required exposure pattern. The substrate exposure apparatus can thus be iteratively used.
The substrate exposure apparatus provided by the present invention comprises a display apparatus and a control system. The display apparatus is used to display the pattern to be transferred to the photoresist. The control system is used to control the pattern displayed by the display apparatus.
In the substrate exposure apparatus provided by the present invention, the display apparatus comprises a non-self luminescent display such as a liquid crystal display (LCD) or a self-luminescent display such as an organic light emitting diode display (OLED), a polymer light emitting diode display (PLED), a plasma display panel (PDP) and a field emission display (FED). The above liquid crystal display further comprises a non-self luminescent liquid crystal display panel and a light source module to provide the exposure light source.
In the present invention, the substrate exposure apparatus performs a contact mode or a non-contact mode exposure process. A protect film is used in contact with the photoresist in the contact mode substrate exposure apparatus. A lens set is selectively located between the display apparatus and the photoresist in the non-contact mode substrate exposure apparatus.
Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.